The term “coffee bean” collectively refers to the seeds (coffee seeds) that are obtained by the process (refining process) of removing the pulp and the skin from the berries (known as coffee berries or coffee cherries) of Coffea plants of the family Rubiaceae and the beans that are produced from these. Of these, “green” coffee beans are coffee beans that have not yet passed through a roasting process, which is a process in which the coffee beans are roasted by heating, and “roasted” coffee beans are coffee beans that have been roasted.
The roasted coffee beans are ground and then infused with hot water, or an extraction liquid such as water, that is extracted by filtration using a filter material such as filter paper or mesh, and the extract that is obtained is taken as a coffee beverage.
The demand for coffee beverages as pleasure beverages continues to grow and diversify. For this reason, there is an interest in diverse coffee beverage products that for example have different flavors and aromas than conventional coffee beverages. Accordingly, it is desirable that the flavors and aromas of coffee beverages are improved so that many types of products may be produced.
One conceivable way to improve the flavor and aroma of coffee beverages is to improve the flavor and aroma of the coffee beans. For example, one feasible way to improve the flavor and aroma of coffee beans is to change to the heating temperature, heating time, and pressure, etc. in various ways during roasting, and in fact, coffee beans having good flavor and aroma have been produced in this way.
Simply changing the various conditions under which roasting is carried out, however, is not sufficient to improve the flavor and aroma of the coffee beans.
Accordingly, it was thought that the flavor and aroma of coffee beverages can be improved by adding flavor and aroma components to coffee beans that have already been roasted (see Patent Document 1).
Specifically, ground green coffee beans are inoculated with and fermented by Aspergillus oryzae and then roasted, and the flavors and aromas that are produced at this time are extracted and added to roasted coffee beans. The extracted flavors have a strong coffee aroma and are without the flavors and aromas peculiar to fermentation, and thus good coffee flavor and aroma can be added to the roasted coffee beans that are infused with these aroma and flavor components, and this allows the flavor and aroma of the coffee beans to be improved.
Patent Document 1: JP H1-112950A (see pg. 1)